In article ,
says...

"iBoaterer" wrote in message
...

In article ,
says...

On Tue, 3 Sep 2013 11:52:03 -0400, iBoaterer
wrote:

In article ,
says...

On Tue, 3 Sep 2013 09:49:34 -0400, iBoaterer
wrote:

What you don't realize is that many bridges carrying interstate
traffic
were never engineered for that weight and frequency of traffic
loads.
That is but one problem.

Why not? They were originally designed for trucks carrying tanks.

Now where on earth do you get THAT idea from???

The original purpose of the interstate highway system and the
original
design guidelines

In many cities, the interstate highways are being added and have been
added. The original guidelines no longer stand, and the fact is that
city bridges have been re-purposed to use for interstate traffic that
they were never intended nor designed to hold.

-----------------------------------

An example would be .......... ??

No problem!

http://tinyurl.com/kn9udaf

Which in part, after a good explanation of old bridges being fracture
critical, states:

Washington state has much incentive to finish the repairs quickly. I-5
is the primary highway corridor along the Pacific Coast, carrying an
average of 71,000 vehicles including 10,000 trucks a day, which will
have to endure lengthy and costly detours until the bridge is repaired.

U.S. Transportation Secretary Ray LaHood announced Friday that $1
million in emergency federal funds would be available to help repair the
bridge.

But the bridge will reopen with the same narrow lanes and low clearances
it always had ? it predates the interstate system and was not
constructed to federal standards for interstates. Many of such bridges
on the interstate system, including this one and others on I-5, were
?grandfathered in,? said Sean McNally, a spokesman for the American
Trucking Associations, an industry group. ?This is designed to a
different era,? he said.